The invention relates to an improved corner seal member for use in a rotary internal combustion engine.
Prior corner seals, shown in FIG. 1, are formed with an apex seal groove 2 and without any other cavity. During operation, the apex seal groove 2 is supplied with pressure gas 5 through the space between the rotor housing 3 and the rotor 4. Although the gas pressure acts against the groove surface, the corner seal is too thick in the portions a and b and too rigid to widen outwards. Therefore, the gas pressure in the apex seal groove will escape through the clearance between the corner seal 1 and the rotor 4 into the adjacent working chamber. This leads to considerable pressure loss.